In a new video released by the GRAMMY Museum on Wednesday, the 25-year-old pop superstar reveals that she felt anxiety throughout a relationship -- that is believed to have been with the One Direction frontman -- that inspired "Out of the Woods."

Swift sits at a piano as she talks openly about her former relationship with the 21-year-old singer, which is from her Sept. 30th acoustic performance at the Clive Davis Theater in Los Angeles, California.

"I'm going to play you a song about a relationship I was in that the number one feeling I felt in the whole relationship was anxiety," she says. "Because it felt very fragile, it felt very tentative. And it always felt like, 'Okay, what's the next road block? What's the next thing that's gonna deter this? How long do we have before this turns into just an awful mess and we break up? Is it a month? Is it three days?'"

"And so, you know, I think a lot of relationships can be very solid and that's kind of what you hope for, for it to be solid and healthy but that's not always what you get," she adds. "And it doesn't mean that it's not special and extraordinary just to have a relationship that's fragile and somehow meaningful in that fragility."

"So this is a song that I wrote with Jack Antonoff [from indie rock band Fun] and it's called 'Out Of the Woods,'" she says, before belting out a stripped-down version of the song that's rumored to be about Styles.

Watch the full video below.

Swift started dating Styles in November 2012, but quickly called it quits in January 2013 after they reportedly got into an argument during a post-holiday vacation in the British Virgin Islands.

Last November, Styles spoke up about the songs Swift penned about him on her 1989 album in a Google hangout chat on the band's YouTube channel.

"We write from personal experience, and I think everyone does, so it would be hypocritical of us to be like, 'Oh you can't write about us,'" he said about what it feels like to have someone write a song about you. "And [Taylor's] really good, so they're good songs. I'm really lucky in that sense."

Looks like the singer has taken a cue from his ex-girlfriend, however. Earlier this month, One Direction released "Perfect," their newest single from their upcoming album, Made in the A.M.. With lyrics like "And if you're looking for someone to write your breakup songs about, baby, I'm perfect," fans are convinced the song is about Swift. Watch the video below to hear more.